* The leader is selected by picking the first reachable member, but in
#13875 we had to let the self member be unreachable in the Reachability
table and that was not considered in the logic of the leader selection.
* That means changed behavior that is unwanted, especially when there
is only one node left the leader could be evaluated to None instead
of Some(selfUniqueAddress).
* Note that #13875 has not been released yet.
* When new uid is seen in join attempt we can down existing
member and thereby new restarted node will be able to join
in later retried join attempt without relying on auto-down.
* Skip observations from downed node (quarantined is marked down immediately)
in convergence check
* Skip observations from downed node when picking "reachable" targets for gossip.
* This also means that we must accept gossip with own node marked as unreachable,
but that should not be spread to the external membership events.
* because it is not referentially transparent; normally we reserved parens for
side-effecting code but given how people thoughtlessly close over it we revised
that that decision for sender
* caller can still omit parens
* Getter for CurrentClusterState in Cluster extension, updated via
ClusterReadView
* Remove lazy init of readView. Otherwise the cluster.state will be
empty on first access, wich is probably surprising
* Subscribe to several cluster event types at once, to ensure *one*
CurrentClusterEvent followed by change events
* Deprecate publishCurrentClusterState, was a bad idea, use sendCurrentClusterState
instead
* Possibility to subscribe with InitialStateAsEvents to receive events corresponding
to CurrentClusterState
* CurrentClusterState not a ClusterDomainEvent, ticket #3614
* The previous one-way hearbeat was elegant, but comlicated to
understand and without giving much extra value compared to this approach.
* The previous one-way heartbeat have some kind of bug when joining
several (10-20) nodes at approximately the same time (but not exactly
the same time) with a false failure detection triggered by the extra heartbeat,
which would not heal.
* This ping-pong approach will increase network traffic slightly, but heartbeat
messages are small and each node is limited to monitor (default) 5 peers.
* Revert the change introduced in
https://github.com/akka/akka/pull/1738/files
* The cleanup/improvements aside of the actual
feature is not reverted by this patch
* Clarify the documentation
* Replace (deprecate) akka.cluster.auto-down config setting with
akka.cluster.auto-down-unreachable-after
* AutoDown actor that keeps track of unreachable members
and performs down from the leader node when they have been
unreachable for the specified duration
* Migration guide
* Replace unreachable Set with Reachability table
* Unreachable members stay in member Set
* Downing a live member was moved it to the unreachable Set,
and then removed from there by the leader. That will not
work when flipping back to reachable, so a Down member must
be detected as unreachable before beeing removed. Similar
to Exiting. Member shuts down itself if it sees itself as
Down.
* Flip back to reachable when failure detector monitors it as
available again
* ReachableMember event
* Can't ignore gossip from aggregated unreachable (see SurviveNetworkInstabilitySpec)
* Make use of ReachableMember event in cluster router
* End heartbeat when acknowledged, EndHeartbeatAck
* Remove nr-of-end-heartbeats from conf
* Full reachability info in JMX cluster status
* Don't use interval after unreachable for AccrualFailureDetector history
* Add QuarantinedEvent to remoting, used for Reachability.Terminated
* Prune reachability table when all reachable
* Update documentation
* Performance testing and optimizations
Check VectorClock for common case first and cache hashCodes. See #3441
Make ClusterDaemon a bit more testable. See #3441
Changing VectorClock and GossipOverview to TreeMaps. See #3441
Make VectorClock private[cluster] and remove unused code. See #3441
* Otherwise, if the Welcome message is lost, other nodes
in the cluster will send HeartbeatRequest and it will start
sending heartbeats without being a real member and the lost Welcome
is not detected by the other members in the cluster
* Removed leader commands for Shutdown and Exit
* Member shutdown itself when it sees itself as Exiting
* Singleton cluster with status Exiting will shutdown itself,
in case the Exiting gossip never arrives
* Exiting member not part convergence check
* Exiting member is removed by leader (on convergence) when the
exiting member is in the unreachable set, i.e. sucessfully shutdown
* Reverted the change made for #3266, i.e. Exiting is
detected as unreachable again.
* Adjust ClusterSingletonManager to new Exiting behaviour
* Fix bug in HeartbeatSender, which caused it to continue to
send heartbeats to removed nodes, instead of rebalancing
* Refactoring of leaderActions method
* Leaving section in docs
* Assign internal upNumber when member is moved to Up
* Public API Member.isOlder
* Change cluster singleton to use oldest member instead of leader
* Update samples and docs
* When seen same the gossip chat is initated with GossipStatus
message containing the vclock only
* Remove conversation flag in GossipEnvelope
* Ordinary tell instead of actorSelection when replying
